Being able to go into a meeting and talk about project requirements is sometimes difficult when you do not know much about what the client needs. The clients always like to use that time to figure out what their department wants to get out of the new product. As the lead application developer, you have to keep the client(s) focused.

What are some techniques that you could use in the meeting that would benefit everyone, by keep the client from wasting your valuable time, and still make progress documenting project requirements in the meeting?